01/10/2011
CURRENT EHV-1 SITUATION:
September 26, 2011: No New Cases
Current Situation Summary
Tuolumne County Index Premises:
8 horses confirmed positive for the neuropathogenic strain of EHV-1
Affected premises under quarantine since September 12, 2011
6 with neurologic signs, 2 with fever only
1 of the 8 confirmed positive cases was euthanized.
All infected horses are isolated and enhanced biosecurity measures implemented.
All exposed horses on the premises are being monitored and temperatures monitored twice daily.
Owners of horses which have visited the premises during a two week period prior to start of the outbreak have been contacted by CDFA and asked to isolate and monitor their exposed horse(s) for 14 days.
Epidemiologic investigations reveal no link to the Sonoma September 2011 or the May 2011 Cutting Horse Outbreaks.
San Joaquin County Secondary Exposed Premises
2 horses confirmed positive for the neuropathogenic strain of EHV-1
Both horses were exposed to the virus on September 4-10, 2011, while visiting the Tuolumne county premises
Premises under quarantine since September 15, 2011
One horse with neurologic signs and the other with fever only.
Epidemiologic investigation conducted by CDFA reveals minimal risk of disease spread beyond this facility due to early detection of disease and immediate isolation of horses post exposure.
PREVIOUS UNRELATED CALIFORNIA EHV-1 OUTBREAKS
September 2011 Outbreak
Single Sonoma County premises affected
3 horses confirmed positive for neuropathogenic strain of EHV-1
One neurologic and 2 febrile only
Neurologic horse died
13 exposed horses were temperature monitored twice daily and observed for clinical signs of disease. None of the 13 ever demonstrated clinical signs of disease.
Epidemiologic Investigation revealed no link to the May 2011 outbreak
Quarantine implemented on August 23,2011
Situation contained and quarantine release on September 13, 2011
May 2011 Outbreak
400 horses exposed to neuropathogenic strain of EHV-1 at the National Cutting Horse Association (NCHA) Western National Championship held in Ogden, Utah April 30-May 8, 2011
All 54 California exposed horses were isolated, temperature monitored twice daily and observed for clinical signs of disease.
22 California horses were confirmed positive for the neuropathogenic strain of EHV-1.
Positive horses resided on 14 premises in 12 counties.
8 displayed neurologic signs, 13 with fevers only and 1 with respiratory signs only.
June 20, 2011 California declared containment of the EHV-1 outbreak associated with the Ogden, UT cutting horse event
